1. Field of the Invention
The present invention relates to an adhesive composition, to films made therefrom, to a method of making such compositions and films, and to products made therefrom. In another aspect, the present invention relates to adhesive composition comprising a terpolymer of an .alpha.-olefin, carbon monoxide and an ethylenically unsaturated carboxylic ester monomer, and further comprising a thermosetting resin, to films made therefrom, to a method of making such compositions and films, and to products made therefrom.
2. Description of the Related Art
Decorative laminates prepared by heat and pressure consolidation have been produced commercially for a number of years, and have found widespread acceptance in the building and furniture industry as counter and table tops, bathroom and kitchen work surfaces, wall paneling, partitions and doors. Such decorative laminates can be described as containing a number of laminae that are consolidated to form a unitary structure carrying a surface decoration which can range from something as simple as a solid color to something as complex as an embossed simulated wood grain finish.
More specifically, a decorative laminate generally comprises plural layers of synthetic resin impregnated paper sheets consolidated or bonded together into a unitary structure under heat and pressure. In normal practice the decorative laminate assembly, from the bottom up, consists of a core of one or more sheets impregnated with phenolic resin, above which lies a decorative sheet impregnated with melamine resin.
The core or base member functions to impart rigidity to the laminate and usually comprises a solid substrate which may or may not be formed prior to the initial laminating step. Prior to stacking, the sheets of the core member are impregnated with water alcohol solution of phenol formaldehyde, dried and partially cured in a hot air oven, and finally cut into sheets. Examples of such a base or core member include a plurality of sheets of 90 to 150 pound ream kraft paper impregnated throughout and bonded with a substantially completely cured phenolic resin which has been converted to the thermoset state during the initial laminating step, a precured plastic laminate, such as glass fiber-reinforced thermoset polyester resin laminates and the like, a wood product, such as hardboard, woodwaste or particle boards, plywood, and the like, a meneral base board, such as cement-asbestos board, sheet rock, plaster board, and the like, or a combination of these substrates.
The decorative sheet generally functions to give an attractive appearance to the laminate, and also gives the panel its surface characteristics (i.e. resistance to chemical agents, to heat, to light, to shock and to abrasion). It is generally high quality 50 to 125 ream weight, pigment filled, alpha cellulose paper that has been impregnated with a solution of melamine-formaldehyde resin, dried and partially cured, and finally cut into sheets. The decorative sheet, prior to impregnation with the resin, may be of a solid color or may comprise a decorative design, or a photo-gravure reproduction of natural materials, such as wood marble, leather, etc.
The decorative laminate is generally obtained by placing the resin impregnated core and decorative sheets between steel plates and subjecting the laminate stack to temperatures in the range of about 200.degree. F. to about 350.degree. F. and pressures in the range of about 800-1600 psi for a time sufficient to consolidate the laminate and cure the resins (generally about 25 minutes to an hour). This causes the resin in the paper sheets to flow, cure and consolidate the sheets into a unitary laminated mass referred in the art as a decorative high-pressure laminate. Continuous methods are also know for making decorative laminates.
Generally, more than one laminate is formed at one time by inserting a plurality of assembled sheets in a stack with each assembly being separated by a release sheet which allows the individual laminates to be separated after consolidation.
Finally, the decorative laminates so formed are then bonded to a reinforcing substrate, such as plywood, hardboard, asbestos board, particle board or the like, by the use of adhesives such as contact adhesives, urea-formaldehyde, white flues (polyvinyl acetate emulsions) hot melts, phenolic or resorcinol-formaldehyde epoxy, coal tar, animal glues, and the like. The glues vary in their cost and reliability. Very commonly the type of glue used in the industry is either a solvent based contact adhesive, or a water-based contact adhesive. An example of a common specific glue used is a polyvinyl acetate emulsion contact adhesive.
While these water-based or solvent-basedthis polyvinyl acetate emulsion glue are inexpensive and reliable, they must be applied at the time of application of the decorative laminate to the substrate since they set up in relatively short order, and are applied in liquid form which may cause application difficulties.
There is a need in the art for an adhesive which can be applied to the decorative laminate far in advance of adhering the decorative laminate to the substrate.
There is another need in the art for an adhesive which does not need to be applied in liquid form.
These and other needs in the art will become apparent to those of skill in the art upon review of this specification, including its drawings and claims.